Slack-adjuster for railway-brakes.



C. 07 ANDERSON. SLAGK ADJUSTER FOR RAILWAY BRAKES.

APPLLGATION IILBD APB. 14, 1913.

1,125,035. Patented Jan. 19, 1915.

wifmemo 2/ UNITED sTArjes 1 YAJV ri:;i\Ifrl OFFICE.

CHARLES 0. .ANDERSON,

or OMAHA, NEBRASKA, AssIGNon., BY MEsNEAssIGNMEN'Ts, or, Two-Turnus To L. D. SPAULDING- sLAoK-AngrUs'rER Fon RAiLWAY-BR'AKES.

Application-filed April V14, 1913. Serial No. 761,055. Y

lbrake rigging andcompensating for wear thereof, especially for wear of the brakeshoes. l

It is the object of my invention to pro.-

vide a simple, reliable, durable and economical mechanism for this purpose.

Constructions embodying my invention are illustrated in the accompanying drawings, wherein- Figure 1 1s a side view of the adjusting 'mechanism and the associated parts of the 'f Fig. 4 is a detail during brake-rigging, Fig. 2 is a longitudinal horizontal section of the adjuster, thesection being on the plane of the line w-m of Fig. 1, Fig. 3 is a detail end view of the same,

section through the clutchparts, taken on the same' plane as in Fig. 2, and Fig. 5 is a detail transverse section' on the line 'z/-y of Fig. 2, illustrating the assembling of the clutch-sleeve and head. Referring to Fig. v1, there is shown a part of the frame l of a truck, brake-shoes 2,`

heads. 3 carrying the shoes, hangers 4 for supporting the heads, dead and live trucklevers 5 and 6, a brake-rod 7 for applymg truck-lever, and a release spring 8 for actuating the'live-lever to release the brakes. All of the foregoing parts are of ordinary -construction and arrangement and operate in a Well-known manner.

' In the illustrated construction my slack- 4 adjusting mechanism provides a variable connecting member between the lower ends of the dead and live truck-levers 5 and 6, and depends for its operation upon the vary? Aing angular relations between one of the truck-levers and said connecting member the application and releasing of the brakes, the length of the connecting member being automatically changed to compensate for wear of theparts.

The connecting member comprises three parts, which are movable relatively to each other and are arranged serially between the connectedends of the truck-levers.` The said Specication of Letters Patent.

Patented Jan. 19, 1915'.

parts are the end-pieces or heads 9 and 10,

and the intermediate part or threaded rod 11. The head 9 is `forked' at one end and straddles the dead-lever 5, being pivotally4 connected therewith by the pin 12. The

other end of said head is of tubular form and `is internally threaded to receive the threaded part of the rod 11. ,The head 10 is also forked Vat one end, the forked portion straddling the live-lever 6 and being pivotally connected therewith by the pin 13. The opposite end of the head 10 has a cylindrical recess therein in which thejplain cylindrical end of the rod 11 fits slidably and rotatably.

Upon the central part of the rod `11 is secured a hexagonal collarV 14, for use in rotating the rod manually when the mechanism is assembled, or when it is reset after a `period of operation. A conical clutch,-

collar 15 is also secured upon the rod, ad-

jacent to the end ofthe head 10, and between the headl and clutchcollar aspring 16 is disposed around the rod. t

A clutch-sleeve 17 fits revolubly upon the 'end portion of the head 10 and extends out over the clutch-collar 15 and springl so as to inclose them. The portion of the sleeve adjacent to the.'collar 15 is of conical form so that the collar will lit therein, and the collar is normallyheld in frictional engagement with the sleeveby the pressureof the spring 16. The portion ofthe sleeve ex tending beyond the collar tseasily upon the rod v11 and is provided with a packingring 18 disposed in an annular grooveadjoining the rod, as shown. The other end of the sleeve has a similar packing-ring 19 which it's against the head 10. On the latter end ofthe sleeve are two yprojecting lips 20 which are grooved annular-lyl on their inner sides, so that they will it over the lugs 21 on the sides of the head 10. `In assembling the vhead and sleeve, the latter is passed longitudinall over the head with the lips 20 not in ongitudinal alinement with the lugs 21. After the endiof the sleeve engages the lugs the sleeve is rotated as indicated in Fig. 5 so that the lugs pass into Vthe annular grooves in the lips. The sleeveand Vhead are thusV retained in fixed longitudinal relation to each other, but so that the sleeve may be rotated relatively to the head. Y

On the side of the sleeve adjacent to one ment of the bell-crank, the pin 27 merely' of the lips 20 is a laterally projecting lug from which the spaced parallel jaws 22 extend out longitudinally of the sleeve. A bell-crank 23 is pivotally mounted on the projecting end-portion of the pin 13. The bell-crank is retained on the pin by means of a nut 26 screwed onto the end of the pin, and a spring 24 is disposed around the pin between the nut and bell-crank, as shown in Figs. 2 and 3, said spring frictionally engaging the bell-crank to `prevent undue movement and rattling of the same. One arm of the bell-crank extends approximately horizontally and has at its end a ball 25 which fits between the jaws 22 on the clutch-sleeve. The other arm of the bellcrank extends upwardly adjacent to the truck-lever fulcrum-pin 27 and is, in effect, forked so as to straddle the projecting end of said pin. One side of the forked end of the arm is formed by a finger 28, the same having a threaded stem which is screwed through the main part of the arm, so that by turning the same the space between the forks. may be varied. A suitable lock-nut 29 is provided for holding the threaded stem and finger in adjusted positions.

By suitable adjustment of the linger 28, the width of the spacebetween the forks is made such that a normal movement of the truck-levers, in applying and releasing the brakes, may occur without causing movepassing from one side of the space tothe other. Vhen, however, a movement of the levers greater than the normal is required to apply the brakes, then the bell-crank will be moved in one direction as the brakesare applied, and moved in the opposite direction when the brakes are again'released, the

amount of movement being proportional to the excess movement 'of the levers over the normal. The-said movements of the bellcrank are communicated to the clutch-sleeve and cause an oscillating or alternating rotative movement thereof about the-head 10. When the brakes are in release position, the connecting member formed 'by the heads 9 and 10 and the rod l1 is not under compression, and the spring 16 pressing against the clutch-collar holds the end of the rod 11 slightly away from the bottom of the recess in the head 10, as shown in Fig. 2, the' clutch-collar and sleeve being held in frictional engagement with each other. As the brakes aril moved to applied position, howc\ er, the connecting member is placed under a compressive sti-css. and before the application of the brakes is completed the spring ll' vields until the end of the rod 1l engages the bottom of the recess in the-headfas shown in Fig. 4. When in the latter position, the clutch-collar is disengaged from the clutch-sleeve, and the rotative movement of the sleeve caused at this time by the bellcrank will have no tendency to turn the clutch-collar and the rod 11. Then as the brakes are released the spring 16 moves the rod and; clutch-collar longitudinally away from the head until the collar engages the sleeve, so that the rotative movement of the sleeve occurring at this time is communicated to the collar and the rod. The rod is thus rotated more or less relatively to both of the heads 9 and 10. The relative rotation between the head 9 and the threaded part of the rod lengthens the connecting member slightly and thus compensates for a part. of the excessive slack which permitted the increased or excessive movement. of the trucklevers necessary. toactuate the bell-crank and clutch-sleeve. Subsequent application and releasing of the brakes will cause further compensatory lengthening of the connecting member, until the movement of the truck-levers is reduced to the normal, after which no furtherv action of the adjusting mechanism will occur until ,there is further wear of the parts with a consequent increase in the amount of movement of the trucklevers necessary to apply the brakes.

The rotation of the threaded rod to lengthen the connecting member, being made when themember is under only a slight longitudinal stress, requires but a relatively small force, which is supplied by the release spring 8. Accidental turning of the threaded rod is prevented at all times, since the Jfriction between the threaded parts when the brakes are applied is too great to permit relative movement of the said parts, and when the brakes are in release position the clutch-sleeve is held stationary by the bell-crank, while the sleeve and clutch-collar are held in en agement by the spring 16 with a force su icient to prevent turning of the rod.

f The hollow portion of the head 9 may be filled with a lubricant to facilitate the turning of the rod. -It will be noted also that the movements ofthe rod are always outward from said head except when the mechanism is being reset before applying new brake-shoes, so that there is no tendency to carry foreign matter between the threaded parts to interfere with their movement. Lubricating material may also be placed within the clutch-sleeve to facilitate free movement of the same and the parts inclosed by it, and the packing-rings 18 and 19 serve eifectually to exclude foreign matter from within the sleeve.

By the use of the frictional clutch members for actuating the threaded rod, it is not necessary that there be any considerable ex*- cess of slack in the brakes before the mechalevers which results in a Acorresponding movement of the clutch-sleeve, however iooA lois` ini ist"

slight, will be communicated thereby to the the adjuster' under service conditions, it has been observed that no measurable variation ot slack occurred during the period 1n which a set of brake-shoes Were Worn out.

Now, having described my invention, what I claim and desire to secure by Letters Patent 1s:

l. In a slack adjuster for brakes, brakelevers a member connectinfT said levers. 7 b A 4 said: member comprising end-parts connected with the respective levers, and an intermediate threaded part rotatable to vary the length of kthe member, a clutchmember ixedl y secured to the threaded part, a second clutch-member engageable with the first and held in fixed longitudinal relation to one of the end-parts, means for actuating said second clutch-member in directions alternating as the brakes are applied and released, and resilient means normally holding the clutch-members in engagement with each other but yieldable to permit disengagementv of the cluch-members while the actuating means moves in one direction.

2. Ina slack-adjuster forvbrakes, a variable connecting member comprisingy endparts and an intermediate threaded part rotatable to change the length of the member, a clutch-member secured to the'threaded part, an actuating clutch-member held in fixed longitudinal'relation to `one of the endparts, means for rotating ysaid .actuating member in directions alternating as the brakes are applied and released, andmeans for moving the threaded member longitudinally relative to the actuating clutchmember to engage the clutch-members-With each other as the brakes are released.

3. In a slack-adjuster for brakes, a brakelever connection comprising a rod having a threaded portion and carrying a clutchmember, a head engaged by the threaded rod-portion, and a head having an abutment to engage an unthreaded part of the rod, an

oscillating clutch-member carried by the latter head, and means for normally 'holding the rod away from the abutment and with the clutch-member carried by the rod in engagement with the oscillating clutch-member, the clutch-members being disengaged when the rod is engaged with the abutment.

Li. In a slack-adjuster for brakes, a brakelever connection including a pair of threaded parts relatively rotatable to vary the length of the connection, lorfgitudinally upon one of the threaded parts. a spring tending to separate said threaded part and said slidable part. said parts being movable toward each other as the brakes are applied, clutch-members carried by said parts and arranged so as to be disengaged as the parts move toward each other and to be engaged as the spring moves and a part slidable `vary the length of the parts away from each other, and means for actuating one of the clutch-,members as the brakes are released. l

In aslack-adjusterfor brakes, a brakelever connection comprising ahead having a threaded part, a threaded rod engaging said part, and a head slidable longitudinally of the rod and having an abutment to limit the longitudinal movement, a spring` tending to disengage the rod andabutment, clutch-members carried respectively Yon the rod and thei'latt'er head, the one clutclr' member being rotatable relatively to the head, and means for oscillating said clutchmember, the clutch-members being engageable when the rod and abutment are out of engagement, and being disengaged when the rod and abutment are engaged.

6. In. a slack-adjuster for brakes, a

.clutch-member held in fixed longitudinal relation to the latter head, means for rotating the latter clutch-member in directions alternating as the brakes are applied and released, and resilient means for moving the rod longitudinally to engage the clutchmembers with each other as the brakes are released,fsaid means being yieldable to enable tlie clutch-members kto be disengaged as the brakes'are applied.

7 In a slack-adjuster for brakes, a brakelever connection comprising two heads and an intermediate rod having a screw connection with one of the headswhereby rotation of the rod Will vary the length of the connection, the rod and the other head being connected so as to enable a limited relative longitudinal sliding movement thereof, clutch-members carried bythe rod and the latter head, means for rotating the clutchmember on the head in directions alternating as the brakes are applied and released, and means for moving the clutch-members into engagement with eachotherduring the rotation of the actuating clutch-member in one direction.

8. In a slack-adjuster for brakes, a connecting member having a rotatable part by' movement of which theflength of the mem; ber is variable. a vclutch-member carried b v said part, an actuating clutch-member en- Iqageable with the first` the clutch-members being'separable by longitudinal stress in the connecting member, and means for moving the clutch-members into engagement with each other when the longitudinal stress in the connecting member `is less than a prede termi ned amount.

9. In a slack-adjuster for brakes` a connecting member having a part rotatable to the member, a clutch- 10o 'i I roisl member carried by said rotatable part, an with each other as'the longitudinal stressaetuating clutch-member held in fixed lonin the connecting member is reduced. gitudinal relation to another part ofthe In testimony whereof I have hereunto connecting member and rotatable in direcsubscribed my name in the. presence of two 5 tions alternatillllg as the brakes are alpled Witnesses.

and released t e parts carrying the c utchmembers being movable by longitudinal CHARLES 0' ANDERSUN' stress in the connecting member to separate Witnesses: the clutch-members, and means for moving M.' ENGLER, 10 the said parts to engage the clutch-members M. L. HYDE. 

